By contrast, public health professionals and, we hope, most physicians understand that the scientific and ethical imperative is to reduce net harm to patients and to society, and that demands concern ...for the consequences of both harmful reassurances and harmful actions.2 Gauging the net harm of any clinical communication or policy action regarding the risk of CTE in retired American football players requires consideration of the dangers of needless worry, but balanced against the potential harm of failing to provide patients with a complete appraisal of the likely cause of their symptoms and of the possible consequences of repeated head trauma. No researcher we are aware of has claimed that symptoms in someone with a history of repeated head trauma “inevitably herald an untreatable, degenerative brain disease”.1 Both the primary investigations3 and the few quantitative risk assessments of CTE to date4,5 have been careful to explain that the very high prevalence of CTE found in case series certainly overstates, due to recruitment bias, the incidence of CTE in retired football players. ...reports of some persons with an exposure and without a particular disease, or without exposure but with the disease (as in lifelong smokers who died of food poisoning, or lung cancer in non-smokers), are completely compatible with a true statistical or causal association between an exposure and a disease.
Abstract
Background
We evaluate the cost-effectiveness of the ‘Best Care’ integrated disease management (IDM) program for high risk, exacerbation prone, patients with chronic obstructive pulmonary ...disease (COPD) compared to usual care (UC) within a primary care setting from the perspective of a publicly funded health system (i.e., Ontario, Canada).
Methods
We conducted a model-based, cost-utility analysis using a Markov model with expected values of costs and outcomes derived from a Monte-Carlo Simulation with 5000 replications. The target population included patients started in GOLD II with a starting age of 68 years in the trial-based analysis. Key input parameters were based on a randomized control trial of 143 patients (i.e., UC (n = 73) versus IDM program (n = 70)). Results were shown as incremental cost per quality-adjusted life year (QALY) gained.
Results
The IDM program for high risk, exacerbation prone, patients is dominant in comparison with the UC group. After one year, the IDM program demonstrated cost savings and improved QALYs (i.e., UC was dominated by IDM) with a positive net-benefit of $5360 (95% CI: ($5175, $5546) based on a willingness to pay of $50,000 (CAN) per QALY.
Conclusions
This study demonstrates that the IDM intervention for patients with COPD in a primary care setting is cost-effective in comparison to the standard of care. By demonstrating the cost-effectiveness of IDM, we confirm that investment in the delivery of evidence based best practices in primary care delivers better patient outcomes at a lower cost than UC.
Tackling health inequities both within and between countries remains high on the agenda of international organizations including the World Health Organization and local, regional and national ...governments. Systematic reviews can be a useful tool to assess effects on equity in health status because they include studies conducted in a variety of settings and populations. This study aims to describe the extent to which the impacts of health interventions on equity in health status are considered in systematic reviews, describe methods used, and assess the implications of their equity related findings for policy, practice and research.
We conducted a methodology study of equity assessment in systematic reviews. Two independent reviewers extracted information on the reporting and analysis of impacts of health interventions on equity in health status in a group of 300 systematic reviews collected from all systematic reviews indexed in one month of MEDLINE, using a pre-tested data collection form. Any differences in data extraction were resolved by discussion.
Of the 300 systematic reviews, 224 assessed the effectiveness of interventions on health outcomes. Of these 224 reviews, 29 systematic reviews assessed effects on equity in health status using subgroup analysis or targeted analyses of vulnerable populations. Of these, seven conducted subgroup analyses related to health equity which were reported in insufficient detail to judge their credibility. Of these 29 reviews, 18 described implications for policy and practice based on assessment of effects on health equity.
The quality and completeness of reporting should be enhanced as a priority, because without this policymakers and practitioners will continue lack the evidence base they need to inform decision-making about health inequity. Furthermore, there is a need to develop methods to systematically consider impacts on equity in health status that is currently lacking in systematic reviews.
Systematic reviews have been challenged to consider effects on disadvantaged groups. A priori specification of subgroup analyses is recommended to increase the credibility of these analyses. This ...study aimed to develop and assess inter-rater agreement for an algorithm for systematic review authors to predict whether differences in effect measures are likely for disadvantaged populations relative to advantaged populations (only relative effect measures were addressed).
A health equity plausibility algorithm was developed using clinimetric methods with three items based on literature review, key informant interviews and methodology studies. The three items dealt with the plausibility of differences in relative effects across sex or socioeconomic status (SES) due to: 1) patient characteristics; 2) intervention delivery (i.e., implementation); and 3) comparators. Thirty-five respondents (consisting of clinicians, methodologists and research users) assessed the likelihood of differences across sex and SES for ten systematic reviews with these questions. We assessed inter-rater reliability using Fleiss multi-rater kappa.
The proportion agreement was 66% for patient characteristics (95% confidence interval: 61%-71%), 67% for intervention delivery (95% confidence interval: 62% to 72%) and 55% for the comparator (95% confidence interval: 50% to 60%). Inter-rater kappa, assessed with Fleiss kappa, ranged from 0 to 0.199, representing very low agreement beyond chance.
Users of systematic reviews rated that important differences in relative effects across sex and socioeconomic status were plausible for a range of individual and population-level interventions. However, there was very low inter-rater agreement for these assessments. There is an unmet need for discussion of plausibility of differential effects in systematic reviews. Increased consideration of external validity and applicability to different populations and settings is warranted in systematic reviews to meet this need.
ABSTRACT
State-of-the-art radio observatories produce large amounts of data which can be used to study the properties of radio galaxies. However, with this rapid increase in data volume, it has ...become unrealistic to manually process all of the incoming data, which in turn led to the development of automated approaches for data processing tasks, such as morphological classification. Deep learning plays a crucial role in this automation process and it has been shown that convolutional neural networks (CNNs) can deliver good performance in the morphological classification of radio galaxies. This paper investigates two adaptations to the application of these CNNs for radio galaxy classification. The first adaptation consists of using principal component analysis (PCA) during pre-processing to align the galaxies’ principal components with the axes of the coordinate system, which will normalize the orientation of the galaxies. This adaptation led to a significant improvement in the classification accuracy of the CNNs and decreased the average time required to train the models. The second adaptation consists of guiding the CNN to look for specific features within the samples in an attempt to utilize domain knowledge to improve the training process. It was found that this adaptation generally leads to a stabler training process and in certain instances reduced overfitting within the network, as well as the number of epochs required for training.
Para este estudio de caso el objeto de estudio fueron las necesidades de formación docente que tiene la Región Brunca con respecto a la enseñanza del inglés. Para indagar sobre estas necesidades ...se llevó a cabo una serie de grupos focales y cuestionarios con diferentes participantes del currículo regional: personas expertas, representantes de universidades públicas, empleadoras, docentes y estudiantes, quienes brindaron insumos para un análisis inductivo a través del enfoque cualitativo. Los resultados reflejan que la enseñanza del inglés en la región requiere fomentar la incorporación de elementos de la lingüística aplicada crítica (LAC), las Tecnologías de Información y Comunicación (TIC), y la enseñanza del inglés con fines específicos en las aulas (EFS). Se concluye que un programa de especialización en la enseñanza del inglés, que tome en cuenta los elementos mencionados, puede repercutir positivamente en la calidad de la educación, la competitividad y la formación humanística requerida para generar mayores niveles de bienestar social y económico en la zona.
In Part 1 of this article we developed an approach for the calculation of cancer effect measures for life cycle assessment (LCA). In this article, we propose and evaluate the method for the screening ...of noncancer toxicological health effects. This approach draws on the noncancer health risk assessment concept of benchmark dose, while noting important differences with regulatory applications in the objectives of an LCA study. We adopt the central tendency estimate of the toxicological effect dose inducing a 10% response over background, ED10, to provide a consistent point of departure for default linear low‐dose response estimates (βED10). This explicit estimation of low‐dose risks, while necessary in LCA, is in marked contrast to many traditional procedures for noncancer assessments. For pragmatic reasons, mechanistic thresholds and nonlinear low‐dose response curves were not implemented in the presented framework. In essence, for the comparative needs of LCA, we propose that one initially screens alternative activities or products on the degree to which the associated chemical emissions erode their margins of exposure, which may or may not be manifested as increases in disease incidence. We illustrate the method here by deriving the βED10) slope factors from bioassay data for 12 chemicals and outline some of the possibilities for extrapolation from other more readily available measures, such as the no observable adverse effect levels (NOAEL), avoiding uncertainty factors that lead to inconsistent degrees of conservatism from chemical to chemical. These extrapolations facilitated the initial calculation of slope factors for an additional 403 compounds; ranging from 10−6 to 103 (risk per mg/kg‐day dose). The potential consequences of the effects are taken into account in a preliminary approach by combining the βED10) with the severity measure disability adjusted life years (DALY), providing a screening‐level estimate of the potential consequences associated with exposures, integrated over time and space, to a given mass of chemical released into the environment for use in LCA.
Following a comprehensive evaluation of the health risks of radon, the U.S. National Research Council (US‐NRC) concluded that the radon inside the homes of U.S. residents is an important cause of ...lung cancer. To assess lung cancer risks associated with radon exposure in Canadian homes, we apply the new (US‐NRC) techniques, tailoring assumptions to the Canadian context. A two‐dimensional uncertainty analysis is used to provide both population‐based (population attributable risk, PAR; excess lifetime risk ratio, ELRR; and life‐years lost, LYL) and individual‐based (ELRR and LYL) estimates. Our primary results obtained for the Canadian population reveal mean estimates for ELRR, PAR, and LYL are 0.08, 8%, and 0.10 years, respectively. Results are also available and stratified by smoking status (ever versus never). Conveniently, the three indices (ELRR, PAR, and LYL) reveal similar output uncertainty (geometric standard deviation, GSD ≈ 1.3), and in the case of ELRR and LYL, comparable variability and uncertainty combined (GSD ≈ 4.2). Simplifying relationships are identified between ELRR, LYL, PAR, and the age‐specific excess rate ratio (ERR), which suggest a way to scale results from one population to another. This insight is applied in scaling our baseline results to obtain gender‐specific estimates, as well as in simplifying and illuminating sensitivity analysis.
Life‐table analysis can help to gauge the lifetime impacts that accrue from modifications to (age‐specific) baseline mortality. Modifications of interest include those stemming from ...risk‐factor‐related exposures or from interventions. The specific algorithm used in these analyses can be called a cause‐modified life table (a generalization of the cause‐deleted life table). The author presents an approach for approximating that algorithm and uses it to obtain remarkably simplified expressions for approximating three indices of common interest: life‐years lost (LYL), excess lifetime risk ratio (ELRR), and risk of exposure‐induced death (REID). These efforts are restricted to the special case of multiplicative increases to baseline mortality (modeled as an excess rate ratio, ERR). The simplified expressions effectively “break open” what is often treated as a “black‐box” calculation. Several insights result. For a practical range of risk factor impacts (ERRs), each index can be related to the ERR as a function of a baseline summary statistic and a “characteristic number” specific to the population and cause of interest. Conveniently, those numbers help form “rules of thumb” for translating among the three indices and suggest heuristics for extrapolating indices across populations and causes of death.
Epidemiologic studies of uranium miners and other underground miners have consistently shown miners exposed to high levels of radon to be at increased risk of lung cancer. More recently, concern has ...arisen about lung cancer risks among people exposed to lower levels of radon in homes. The current Canadian guideline for residential radon exposure was set in 1988 at 800 Bq/m
3
. Because of the accumulation of a considerable body of new scientific evidence on radon lung cancer risks since that time, Health Canada sponsored a workshop to review the current state-of-the-science on radon health risks. The specific objectives of the workshop were (1) to collect and assess scientific information relevant to setting national radon policy in Canada, and (2) to gather information on social, political, and operational considerations in setting national policy. The workshop, held on 3-4 March 2004, was attended by 38 invited scientists, regulators, and other stakeholders from Canada and the United States. The presentations on the first day dealt primarily with scientific issues. The combined analysis of North American residential radon and lung cancer studies was reviewed. The analysis confirmed a small but detectable increase in lung cancer risk at residential exposure levels. Current estimates suggest that radon in homes is responsible for approximately 10% of all lung cancer deaths in Canada, making radon the second leading cause of lung cancer after tobacco smoking. This was followed by a perspective from an UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) working group on radon. There were two presentations on occupational exposures to radon and two presentations considered the possibility of radon as a causative factor for cardiovascular disease and for cancer in other organs besides the lung. The possible contribution of environmental tobacco smoke to lung cancers in nonsmokers was also considered. Areas for future research were identified. The second day was devoted to policy and operational issues. The presentations began with a perspective from the U.S. Environmental Protection Agency, followed by a history of radon policy development in Canada. Subsequent presentations dealt with the cost-effectiveness of radon mitigation, Canadian building codes and radon, and a summary of radon standards from around the world. Provincial representatives and a private consultant were given opportunities to present their viewpoints. A number of strategies for reducing residential radon exposure in Canada were recognized, including testing and mitigation of existing homes (on either a widespread or targeted basis) and changing the building code to require that radon mitigation devices be installed at the time a new home is constructed. The various elements of a comprehensive national radon policy were set forth.
This workshop was sponsored by the Radiation Protection Bureau of Health Canada, and was held in collaboration with the McLaughlin Centre for Population Health Risk Assessment at the University of Ottawa. We are grateful to Anar Baweja, Barry Hauck, Sonia Johnson, Ed Korpach, and Trevor Stocki for support in organizing and carrying out the workshop. Jack Cornett, Director of the Radiation Protection Bureau, is thanked for his support and encouragement to the workshop. Most of all, we thank all those who attended the workshop and shared their views.
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